An inline refrigerant cleaning system that may be used with a centrifugal compressor containing R123 refrigerant is:

• A. Refrigerant recycling
• B. Desiccant drying
• C. Lubricant separation
• D. Refrigerant injection

Answer: (A)

The main concept is keeping refrigerant clean and reusable by purifying it through an inline cleaning process as part of a recycling system, especially when dealing with R123 in a centrifugal compressor. An inline refrigerant cleaning system is designed to remove moisture, acids, particulates, and trace oils from the refrigerant so it can be reused rather than discarded. For R123, removing these contaminants is crucial because moisture and acids can cause corrosion and degrade compressor performance and seals. By recycling the refrigerant, you recover it, filter and purify it to the required specification, and then reuse it, which is why refrigerant recycling is the best fit.

Desiccant drying only pulls out moisture but doesn’t address other contaminants or recovery/purification; lubricant separation targets oil removal rather than restoring the entire refrigerant charge; refrigerant injection involves adding refrigerant to the system and does not describe cleaning or purification of the recovered refrigerant.